This invention relates to the field of water conditioning systems and is primarily concerned with providing a control system for starting a regeneration cycle at a predetermined time after a predetermined volume of water has been treated.
Heretofore, the majority of water treatment systems have been set for regeneration periods based on a fixed period of time. Such systems include a "skipper wheel" set for the desired number of days between regeneration cycles so that the system regenerates on the prescribed schedule regardless of the amount of water used between regenerations. If the system was set for one, or two, or three days, or more, the regeneration period occurred at the same time on the same daily schedule as prescribed by the skipper wheel setting irrespective of water usage.
At times more water was used than anticipated and this resulted in the system delivering hard water before a regeneration was called for by the skipper wheel setting. At other times, less water was used than was anticipated, but the regeneration cycle proceeded in accordance with the setting with the result that this cycle caused salt in the brine tank to be wasted, as well as water and a resin bed, which was only partially depleted, was regenerated unnecessarily. Such arrangements are illustrated and described in prior Fleckenstein U.S. Pat. Nos. 3,457,792, 3,742,768, and 3,874,412.
Other systems such as shown in U.S. Pat. Nos. 2,078,361, 2,310,978, 3,396,845, 3,509,998, 3,570,520, and 3,891,552 have initiated regeneration after the treatment of a predetermined volume of water. These systems, however, could not control the time of day at which regeneration took place since regeneration was controlled solely by volume of treated water. In some of these systems the time of day when regeneration took place was unimportant since two resin tanks were used, the one being regenerated being phased out of the system and the other tank supplying treated water continuously. Obviously such an arrangement is far more expensive and complex than applicant's arrangement as set forth herein. Furthermore, if a single resin tank is used, it is deemed important to initiate regeneration at a time when little or no water is being used since once the regeneration process beings, only untreated water will be dispensed. Most often regeneration is scheduled to occur in the late evening or early morning hours when the occupants of the house are sleeping and no water usage takes place.